Syphilis and Yaws

There are not, in the whole of medicine, two diseases so similar as syphilis and yaws*—so similar in their clinical manifestations; so similar in their clinical course; so similar in their causal organisms that they cannot be distinguished by any known pathological process one from the other; so similar in their serological reaction that they are the same for the two diseases; so similar in their response to treatment, whether that treatment was one of the earlier medications or the more recent modern treatment by antibiotics; so similar in every respect—one disease almost confined to the people of the temperate zone and the other to the people of the tropical zone; so similar that the question must arise once more: Are they not one and the same disease modified by the climate and the conditions in which they occur ? To arrive at any conclusion the histories that